C++Talk.NET C++ language newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  read / write locks and deadlock detection          C++Talk.NET Forum Index -> C++ language (comp.lang.c++) View previous topic :: View next topic   Author Message Jürgen Devlieghere Guest Posted: Tue Nov 29, 2005 7:29 am    Post subject: read / write locks and deadlock detection Hi, We are creating event-driven multi-threaded applications on a daily basis. To help us solving deadlocks, we implemented a CriticalSection class that does dead-lock detection: an attempt to Enter() the critical section that would cause a deadlock logs the complete deadlock loop (thread / Critical section) and raises an exception. It has helped us a lot in the past. However, to prevent further deadlocks, and to get a higher performance, we want to implement read / write locks. So, we need: - read / write locks - with deadlock detection - the locks should be re-entrant (like a mutex: a thread can ask again for the lock and gets it immediately. There is a counter inside that ensures that the lock is only released after an equal number of calls of Leave() as there were of Enter(). I found a good article about how to implement a read/write lock on MSDN written by Ruediger R. Asche, but that code doesn't support re-entrance by the same thread. Any of you has a reference to a good article / source code / library? I realize there are ways to avoid dead-locks: - work with 1 worker thread (bad performance on multi-processor) - collect data on the higher level and pass that along. That we did for as long as the data still was contained where it belonged. Jürgen Back to top Niklas Norrthon Guest Posted: Tue Nov 29, 2005 10:23 am    Post subject: Re: read / write locks and deadlock detection "Jürgen Devlieghere" <jdv_ommit_all_this (AT) voxtron (DOT) com> writes: Quote: Hi, We are creating event-driven multi-threaded applications on a daily basis. [snip] Try comp.programming.threads. /Niklas Norrthon Back to top peter koch Guest Posted: Tue Nov 29, 2005 10:39 am    Post subject: Re: read / write locks and deadlock detection Jürgen Devlieghere skrev: Quote: Hi, We are creating event-driven multi-threaded applications on a daily basis. To help us solving deadlocks, we implemented a CriticalSection class that does dead-lock detection: an attempt to Enter() the critical section that would cause a deadlock logs the complete deadlock loop (thread / Critical section) and raises an exception. It has helped us a lot in the past. However, to prevent further deadlocks, and to get a higher performance, we want to implement read / write locks. So, we need: - read / write locks - with deadlock detection - the locks should be re-entrant (like a mutex: a thread can ask again for the lock and gets it immediately. There is a counter inside that ensures that the lock is only released after an equal number of calls of Leave() as there were of Enter(). I found a good article about how to implement a read/write lock on MSDN written by Ruediger R. Asche, but that code doesn't support re-entrance by the same thread. Reentrancy is not something you should strive for unless it is absolutely necessary. In my code I do checks when using reentrant mutexes (or critical section or whatever you call the beast) that the mutex is not locked twice by the same thread. The reason is (put briefly) that you better know what your code is up to. But this is all for comp.programming.threads where you should direct your questions. /Peter [snip] Quote: Jürgen Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         C++Talk.NET Forum Index -> C++ language (comp.lang.c++) All times are GMT Page 1 of 1   Jump to: Select a forum C/C++----------------C LanguageC Language (Moderated)C++ Language (Moderated)C++ language (comp.lang.c++)C++ language, library and standards Non-English C/C++ Newsgroups----------------C++ (German)C++ (French)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.